The key to the sentence is the word murder. Whoever was saying the sentence was trying to tell you that he or she had a sister who was murdered just 20 feet from the playing field.
Twenty feet really isn't very much. Most small cars are just 4 feet shorter than 20 feet. That's not much.
So whoever is saying this is saying that the wonders of playing soccer could not overcome the awful feeling he/she must have knowing that his sister died there. Every time the narrator got on the field, he would be reminded of her death.
